Fig. 5.

Co-localization of the eIF4E proteins and their isoforms with PBs and SGs during oxidative stress. The eIF4E1, 2, 3 proteins (green) were ectopically produced in fusion with GFP in U2OS cells. Nineteen hours post-transfection, the cells were treated with 1 mM sodium arsenite for 40 min, fixed and assessed for eIF3B-stained SGs (red) and DDX6-stained PBs (blue). Co-localization of the particular eIF4E with SGs and PBs is demonstrated in the boxed area on the right side of each panel and by the intensity profile measured along the dashed white line within the boxed area. Contrary to heat shock, only the eIF4E1 variants were able to co-localize with both SGs and PBs (a, b). The eIF4E2 protein variants (c–e) co-localized only with PBs. eIF4E3_A (f) was present only in SGs, and eIF4E3_B (g) co-localized with neither SGs nor PBs. Approximately 50 cells transfected with either vector were observed in two independent biological replicates. Scale bar, 20 µm